A potentially beneficial feature for an internal combustion engine is the ability to change the phasing of the engine's camshaft(s) relative to that of the engine's crankshaft for the purpose of changing the phasing of the operation of the engine's intake and/or exhaust valves, and a number of such phase adjustment mechanisms have heretofore been proposed. When a camshaft phase adjustment mechanism is of the electromechanical type, it can be placed under the jurisdiction of an electronic control system for the engine so that an electronic command signal from the control system to the electromechanical mechanism sets the relative phasing of the camshaft(s) to a desired setting within a range of relative phases. Changes in the command signal produce corresponding changes in the relative phasing.
When the engine is used as a powerplant for a motor vehicle, it is especially important for the phasing mechanism to be compact and economical, in addition to being accurate, durable, and responsive. The present invention is directed to a mechanism that possesses these attributes. Further details will be seen in the ensuing description and claims. The detailed description will be given with reference to an accompanying drawing which illustrates the best mode contemplated at the present time in carrying out the invention.